Control arrangement for a swimming pool filter

ABSTRACT

The control arrangement for a swimming pool filter includes two pairs of control valves, the discharge port of the first valve in each pair being coupled to the intake port of the second valve. The intake ports of the first valves are connected by a highpressure conduit to the output end of the filter pump whose input end draws water from the pool. Two low-pressure conduits connect the discharge ports of the second valves to the pool and to a waste line respectively. The filter is connected by by-pass lines to the coupled ports between the valves in each pair. A single operating mechanism is connected to all valves and operates the same in timed sequence in which the valves direct water flow from the pump either through the filter in a first direction to the pool, or through the filter in the opposite direction to a waste line, or ultimately directly from the pool to the waste line.

[ 51 June 20, 1972 [54] CONTROL ARRANGEMENT FOR A SWIMMING POOL FILTER [72] Inventor: Volker Seid, Heilbronn, Germany [73] Assignee: Cillichemie Ernst Vogelmann, Heilbronn,

Germany [22] Filed: Feb. 3, 1971 [21] Appl.No.: 112,315

3,616,915 11/1971 Whitlock ..2lO/l69 Primary Examiner-Reuben Friedman Assistant Examiner-T. A. Granger Anomey-Kelman and Herman [57] ABSTRACT The control arrangement for a swimming pool filter includes two pairs of control valves, the discharge port of the first valve in each pair being coupled to the intake port of the second valve. The intake ports of the first valves are connected by a high-pressure conduit to the output end of the filter pump whose input end draws water from the pool. Two low-pressure conduits connect the discharge ports of the second valves to the pool and to a waste line respectively. The filter is connected by by-pass lines to the coupled ports between the valves in each pair. A single operating mechanism is connected to all valves and operates the same in timed sequence in which the valves direct water flow from the pump either through the filter in a first direction to the pool, or through the filter in the opposite direction to a waste line, or ultimately directly from the pool to the waste line.

10 Claims, 7 Drawing Figures PATENTEUJUKZO m2 SHEET 2 OF 3 Fig. 2

,4 gem/Ts CONTROL ARRANGEMENT FOR A SWIMMING POOL FILTER This invention relates to a control arrangement for a swimming pool and particularly to an arrangement which normally causes water from the pool to be filtered and returned to the pool, but uses water from the pool from time to time for backwashing the filter and discards the resulting slurry.

It is common practice to clean the filter of a swimming pool from time to time by backwashing the filter with water from the pool, and by leading the resulting slurry to a waste line. The filter is not normally accessible for inspection, and it is therefore an object of the invention to provide a control arrangement which switches from normal filter operation to backwashing automatically after a certain period of filter operation.

This object is achieved by means of a control arrangement which includes two pairs of control valves having each an intake port and a discharge port. The discharge port of the first valve in each pair is coupled to the intake port of the second valve. A high-pressure conduit is provided for connecting the intake ports of both first valves to the discharge end of a pump. Two low-pressure conduits may connect the discharge ports of the two second valves to a swimming pool from which the pump draws water and to a waste line respectively. Two by-pass conduits are arranged for connecting the filter for the pool between the couplings in the two valve pairs respectively. The several valves are connected to a single operating device which operates the valves in a timed sequence in which the valves, when connected by the conduits to the pump, the pool, the waste line, and the filter, direct flow of water from the pump in a first stage in one direction through the filter and to the pool, and in a second stage through the filter in the p posite direction and to the waste line. If so desired, pumped water may be led in a third stage from the pump directly to the waste line.

Other features, additional objects, and many of the attendent advantages of this invention will be appreciated readily as the invention becomes better understood by reference to the following detailed description of a preferred embodiment when considered in connection with the accompanying drawing in which:

FIG. I is a flow diagram of a swimming pool equipped with a filter, a circulating pump, and a control arrangement of the invention in a first stage of operation;

FIGS. la and lb diagrammatically illustrate the apparatus of FIG. 1 in second and third operating stages respectively;

FIG. 2 illustrates the control valve assembly of the apparatus of FIG. 1 in elevation, and partly in section;

FIG. 3 shows the pilot valve assembly for the control valves of FIG. 2 in elevational section;

FIG. 4 illustrates the drive arrangement for the pilot valves of FIG. 3 in top plane view; and

FIG. 5 is a developed, elevational, and partly sectional view of the device of FIG. 4.

Referring now to the drawing, and initially to FIG. 1, there is seen a swimming pool 1 connected by a suction line 2 to the intake end of a circulating pump 3. A high-pressure conduit connects the discharge end of the pump 3 to two pairs of control valves 7, 8, and 9, 10, the conduit 15 leading directly to the intake ports of respective first valves 8, 9 in each pair. The discharge ports of the first valves 8, 9 are coupled to the intake ports of the respective second valves 7, 10. The discharge port of the valve 7 is connected by a low-pressure conduit 4 to the pool 1, and a similar conduit 5 connects the discharge port of the second valve 10 to a waste line 6 which may be a sewer or the like. By-pass conduits ll, 12 lead from the coupled ports of the valves in the respective pairs to the two ends of a filter 13.

In the first operating stage of the control arrangement represented in FIG. I by the valves 7-10, the valves 7 and 9 are open, and the valves 8 and 10 are closed. When the pump 3 operates, the valves direct water taken from the pool 1 by the pump 3 through the filter 13 back to the pool 1. Impurities in the water are retained in the filter 13 in a conventional manner, not shown.

FIG. la shows the apparatus of FIG. I in a second operating stage in which the valves 8 and 10 are open, and the valves 7 and 9 are closed. Water discharged from the pump 3 into the high-pressure conduit 15 is directed through the filter 13 in a direction opposite to the flow in the first-described sage so that the previously accumulated cake of impurities is dislodged and swept to the waste line 6.

In the third operating stage illustrated in FIG. 1b, the valves 8, 9, and 10 are open, and the valve 7 is closed. Most of the water drawn from the pool 1 by the pump 3 flows directly into the waste line 6. Only a minor portion of the water stream can pass through the filter 13 because of the flow resistance of the latter, and sweeps residual impurities to the waste line. The mode of operation is not much afiected, if the valve 8 remains closed in the third operating stage.

The control arrangement with which this invention is more specifically concerned is illustrated in FIGS. 2 to 5. Referring initially to FIG. 2, there is seen an assembly which combines the valves 7-10. It includes a unitary housing 14 which is divided into five flow chambers by integral, internal partitions 18. The chambers are arranged in a row. The central chamber 15' communicates with the high-pressure conduit 15 when the valves are assembled with other elements shown in FIG. 1, and two chambers are arranged symmetrically on either side of the central chamber 15, only the chambers l6, 17 on one side being explicitly shown in section. The following description of chambers 16 and 17 will be understood to be equally applicable to the two chambers on the other side of the central chamber.

The partitions 18 form respective valve seats of the valves 9, 10 in the chambers 16, I7 and define ports which directly couple the chamber 16 to the chamber 17, and the latter to the central chamber 15'. Each chamber l6, 17 is provided with a releasable cover 21 having the shape of an inverted cup and sealingly engaging the housing 14 while spacedly extending over the valve seat and the port leading from the associated flow chamber toward the center of the row. A diaphragm 20 of synthetic rubber is attached to each cover 21 in the valve structure so as to bound a valve operating chamber jointly with the cover. A small throttling opening 19 having an effective flow section smaller than that of any portion of the prin cipal flow path through the valve arrangement connects the valve operating chamber of each valve with the next flow chamber toward the center in all positions of the diaphragm 20 which may move between a valve closing position shown in the valve 10 and a valve opening position seen in the valve 9. The diaphragm 20, when in the valve closing position, engages the valve seat and also seals the intake port of the associated valve.

The discharge end of the flow chamber 16 is permanently open to the by-pass conduit 12 leading to one end of the filter l3, and the corresponding flow chamber of the valve 8 on the other side of the central chamber 15 is similarly open to the by-pass conduit 11. The discharge port of the chamber 17 communicates with the lowpressure conduit 5 leading to the waste line 6, and the low-pressure conduit 4 leading to the pool 1 similarly communicates with the chamber of the valve 7. The several conduits are represented in FIG. 2 only by corrugated hose nipples or bells for cemented connections to plastic pipes.

Small hose nipples 221, 222, 223, 224 on the covers 21 communicate with the valve operating chambers in the covers and are connected by flexible tubing (not shown) to corresponding nipples 221, 222', 223', 224 on the housing 24 of the pilot valve assembly seen in FIG. 3 on a scale larger than that of FIG. 2. Partitions 25 divide the interior of the housing 24 into four chambers normally communicating with the nipples 221'-224 respectively, the nipples projecting into each chamber to form a valve seat 26 directed toward an open side of the housing 24. In the illustrated, assembled pilot valve assembly, this open side is covered by a sheet 29 of elastomeric plastic held in place by a cover 28 attached to the housing 24 by screws 32. The sheet 29 engages the partitions 25 so as permanently to seal the several chambers in the housing 24 from each other and may be deflected toward and away from sealing engagement with the valve seat 26 in each chamber.

A cam shaft 31 is joumaled'in brackets integral with the cover 28 and fixedly carries four disc cams 301, 302, 303, 304 in radial alignment with the four valve seats 26. A spherically curved cam follower integral with a motion transmitting plunger 27 is guided in an opening of the cover 28 toward and away from an enlarged portion of the sheet 29 above each valve chamber. The cam followers are held in radial engagement with the cams on the shaft 31 by the resiliency, of the sheet 29, and cause movement of respective portions of the sheet toward and away from the valve seats 26 as the cam shaft 31 revolves.

The chambers of the valves operated by the cams 301,302

are permanently connected by tubing 331, 332 with a small nipple.500 on the conduit 5, and the chambers of the valves operated by the cams 303, 304 are connected by tubing 333, 334 to a small radial nipple 400 on the conduit 4.

In the angular position of the cam shaft 31 shown in FIG. 3 and the corresponding positions of the several cams 301-304 and plungers 27, the control valve assembly is set for operation as illustrated in FIG. 1.

The valve seat on the nipple 224' is sealed by the cam 301 acting on the plastic sheet 29. If the valve 10 was initially in the open position shown in FIG. 2 with reference to the valve 9, thepressure in the valve operating chamber becomes equal to that in the initially connected chambers 16, 17 by throttled liquid flowing through the diaphragm opening 19, and the diaphragm 20 of the valve 10 moves toward the closed position due to its resiliency. When it reaches its relaxed, planar position, it throttles flow between the chambers 16, 17, the pressure in the chamber 17, which is open to the low pressure conduit and the waste line 6, drops toward atmospheric pressure, while the pressure in the chamber 16 and the communicating valve operating chamber of the valve rises toward the pressure in the central chamber and in the high-pressure conduit 15 near the discharge end of the pump 3. The diaphragm of the valve 10 ultimately is firmly pressed against its valve seat by the pressure difference.

It the cam 301 is turned away from the position shown in FIG. 3 and permits the sheet 29 to move away from the valve seat 26 on the nipple 224, the pressure in the operating chamber of the valve 10 is released through the tubing 331 faster than it can be maintained through the throttling opening 19, the relaxing membrane moves away from its valve seat, and is ultimately pushed into the fully open position illustrated in the valve 9 in FIG. 2 by the equalized, relatively high pressure in the chambers 16, 17.

The other valves 7, 8,.9 are opened and closed in the same manner when the associated cams 302-304 turn with the cam shaft 31. As is evident from joint consideration of FIGS. 3 and 2, the open nipples 221' and 223' cause the opening of the valves 7 and 9, while the sealed nipples 222', 224' hold the valves 8 and 10 closed, thereby establishing the flow pattern indicated by arrows in FIG. 1.

The drive mechanism which automatically turns the cam shaft 31 and thereby sets the positions of the control valves 7 to 10 in automatic sequence as shown in FIGS. 1 to 1b is illustrated in FIGS. 4 and 5.

As is best seen in the developed view of FIG. 5, the output shaft of a small synchronous motor 40 of the type employed in electric clocks drives the input member of a first step-down gear'transmission 41 whose output member turns a toothed timing wheel 42 once in 24 hours. 24 Circumferentially distributed axial passages in the wheel 42 are dimensioned for frictionally holding pins 43 in a retracted position in which they project upwardly relatively far from the mounting plate 53 of the drive mechanism and in an operative position in which they are almost flush with the plate 53, only a handle on the operative pin projecting partly from the plate 53.

When in the operative position, the pins 43 engage a roller 44 during rotation of the wheel 42. The roller 44 is mounted "on the free end of a resilient arm 45 which closes a microswitch 451 when depressed by a pin 43. The microswitch 451, when closed, energizes a relay in the feed line of the electric motor which drives the pump 3, the relay, feed line, and pump motor not being shown, since they are entirely conventional. The pump 3 thus operates as long as an operative pin 43 is held by the'wheel 42 within range of the roller 44. The operative pin 43 also engages one of the uniformly spaced notches in the circumference of a second wheel 46 and angularly indexes the wheel 46 as long as the pump is operated by the pin. The wheel 46 drives a second step-down gear transmission 47 whose output member 48 is provided with an axially projecting abutment 49 on its circumference. Once during each revolution of the output gear 48, the abutment 49 engages a mating abutment 51 on a circumferentially toothed coupling wheel 50 which is splined-to the cam shaft 31. A knob 54 fixedly connected to the wheel 50 projects from the mounting plate 53 under the biasing force of a helical compression spring 56 interposed between the knob and the shaft 31 which normally holds the abutment 51 within range of the abutment 49.

As is better seen in FIG. 4, the rim of gear teeth on the wheel 50 has a gap which, in the position of the apparatus seen in FIG. 4, is engaged by gear teeth of a wheel in the first transmission 41'. When the abutment 49 on the slowly rotating out-- put gear 48 engages the abutment 51 on the coupling wheel 50, the latter is turned sufficiently that the transmission 41 may mesh with the wheel 50 and turn the same together with the shaft 31 through 1 revolution until the gap in the toothed rim of the wheel 50 again faces the driving wheel in the transmission 41, and the wheel 50 is stopped by friction, particularly by the braking effect of a spring loaded ball 55 mounted on the plate 53 and radially engaging the knob 54.

The ball 55 also serves as a click stop for releasably arresting the knob 54 and the cam shaft 31 in selected angular positions when the knob is manually depressed against the biasing force of the spring 56 until three circumferentially distributed notches 57 in the knob are in a common radial plane with the ball 55. The notches 57 are arranged in such a manner that the cams 301-304 hold the control valves 7-10 in the positions respectively illustrated in FIGS. 1, 1a, 1b upon engagement of the ball 55 with the notches of which only one is seen in FIG. 5. The ball 55 also holds the knob 54 in the depressed axial position when engaging a notch 57.

During automatic operation of the control system, the pump operates during each day for as many hours as coupling pins 43 are depressed into the operative position in the timing wheel 42. The shaft 31 normally is in the position shown in FIG. 3, and the control valves are in the positions seen in FIGS. 1 and 2. During most of the period of pump operation, water is drawn from the pool 1, cleaned in the filter 13, and returned to the pool. 7

After a period of pump operation determined by the transmission ratio of the second gear transmission 47, the wheel 50 couples the shaft 13 to the motor 40 when wheel rotation is initiated by the output gear 48, and the shaft 31 slowly turns through the valve positions of FIGS. 10 and 1b back to the starting position of FIG. 1. The filter 13 is backwashed, and a portion of the water in the pool 1 is directly pumped into the waste line 6, thereby providing space in the pool for fresh water usually admitted by a float valve in a known manner, not shown. The cams 301-304 are shaped in such a manner that the backwashing position of FIG. 1a is maintained during rotation of the shaft 31 through approximately 300, whereas draining occurs during an angular movement of the shaft through approximately 30.

The knob 54 provides a manual override which removes the coupling wheel 50 from an axial position of engagement with the output gear 48 of'the second transmission and with the first transmission 41, and permits the shaft 31 to be set manually for any one of the three operating stages. A manually operated switch (not shown) is arranged parallel to the microswitch 451 to permit the pump to be energized during manual operation of the controls if the roller 44 should not .1

be engaged by one of the pins 43. Conversely, two non-illustrated threedway switches operated by the cams 302 and 304 may be arranged in series with the microswitch 451 in an obvious manner, not shown, to deenergize the pump when the valves 8, 9 are simultaneously in the same open position, as shown in FIG. lb, and for thereby preventing water loss from the pool 1 by drainage, if so desired, without otherwise modifying the control arrangement. Alternatively, the cams 301-304 may be shaped to provide only the valve positions shown in FIGS. 1 and la, and such an arrangement may be preferred for pools which can be drained by gravity, or in which the water is replaced from a continuously running spring, the excess water being discharged by an overflow.

It should be understood, therefore, that the foregoing disclosure relates only to a preferred embodiment of the invention, and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purpose of the disclosure which do not constitute departures from the spirit and scope of the invention set forth in the appended claims.

What is claimed is:

l. A control arrangement for controlling flow of water between a swimming pool, a filter, a pump, and a waste line which comprises:

a. two pairs of control valves,

1. each control valve having an intake port and a discharge port; b. coupling means connecting the discharge port of a first valve of each pair to the intake port of the second valve of said pair; c. high-pressure conduit means for connecting the intake ports of said first valves to the discharge end of said P p; d. two low-pressure conduit means for connecting the discharge ports of said second valves to said pool and to said waste line respectively; e. two by-pass conduit means for connecting said filter between said coupling means; and f. single operating means connected to each of said valves for operating the valves in a timed sequence in which the valves, when connected by said conduit means to said discharge end to the pump, to said pool, to said waste line, and to said filter, direct flow of water from said P p 1. in a first stage of said sequence through said filter in a first direction and to said pool, and

2. in a second stage of said sequence through said filter in a second direction opposite to said first direction to said waste line.

2. An arrangement as set forth in claim 1, wherein each of said control valves includes a valve seat and a flexible diaphragm, said operating means including means for generating a pressure differential across said diaphragm and for thereby moving the diaphragm toward and away from a position of sealing engagement with said valve seat.

3. An arrangement as set forth in claim 2, wherein said diaphragm in each valve separates a flow chamber from a valve operating chamber, said valve seat being located in said flow chamber intermediate said intake and discharge ports, said valve being fonned with a throttling passage of much smaller flow section than said ports and said chambers, said passage connecting said operating chamber to said intake port.

4. An arrangement as set forth in claim 3, wherein said means for generating a pressure differential include a pilot valve operatively interposed between each valve operating chamber and one of said low-pressure conduit means, said single operating means include a cam shaft, a plurality of cams mounted on said cam shaft for rotation therewith and respectively associated with said pilot valves, and motion transmitting means connecting each cam to the associated pilot valve for opening and closing the pilot valve when the cam shaft is turned.

5. An arrangement as set forth in claim 4, wherein said operating means include manual means for turning said cam shaft.

6. An arrangement as set forth in claim 4, wherein said operating means include a motor, coupling means interposed between said motor and said cam shaft, and coupling operating means responsive to the duration of said first stage for engaging said coupling means after a predetermined period of water flow from said pump through said filter to said pool.

7. An arrangement as set forth in claim 6, further comprising pump control means for controlling the operation of said pump, said coupling operating means including a first wheel, a speed reducing transmission interposed between said motor and said first wheel for turning said wheel about an axis, a plurality of engaging members circumferentially mountedon said wheel for movement of each engaging member between an operative and an inoperative position, a second wheel, each engaging member when in the operative position and when said first wheel is in a predetermined angular position engaging said pump control means for causing operating of said pump and engaging said second wheel for angularly indexing said second wheel, and motion transmitting means responsive to the angular position of said second wheel for engaging said coupling means.

8. An arrangement as set forth in claim 7, wherein said coupling means include a coupling wheel secured on said cam shaft against rotation while axially movable on said shaft toward and away from an axial position of driving engagement with said transmission.

9. An arrangement as set forth in claim 8, wherein said coupling wheel has a gear rim formed with a gap free from gear teeth, said rim being adapted to mesh with said transmission in said position of driving engagement, said coupling wheel being rotated through substantially l revolution by the meshingly engaged transmission.

10. An arrangement as set forth in claim 1, said timed sequence including a third stage in which flow of water is directed by said control valves directly to said waste line. 

1. A control arrangement for controlling flow of water between a swimming pool, a filter, a pump, and a waste line which comprises: a. two pairs of control valves,
 1. each control valve having an intake port and a discharge pOrt; b. coupling means connecting the discharge port of a first valve of each pair to the intake port of the second valve of said pair; c. high-pressure conduit means for connecting the intake ports of said first valves to the discharge end of said pump; d. two low-pressure conduit means for connecting the discharge ports of said second valves to said pool and to said waste line respectively; e. two by-pass conduit means for connecting said filter between said coupling means; and f. single operating means connected to each of said valves for operating the valves in a timed sequence in which the valves, when connected by said conduit means to said discharge end to the pump, to said pool, to said waste line, and to said filter, direct flow of water from said pump
 1. in a first stage of said sequence through said filter in a first direction and to said pool, and
 2. in a second stage of said sequence through said filter in a second direction opposite to said first direction to said waste line.
 2. in a second stage of said sequence through said filter in a second direction opposite to said first direction to said waste line.
 2. An arrangement as set forth in claim 1, wherein each of said control valves includes a valve seat and a flexible diaphragm, said operating means including means for generating a pressure differential across said diaphragm and for thereby moving the diaphragm toward and away from a position of sealing engagement with said valve seat.
 3. An arrangement as set forth in claim 2, wherein said diaphragm in each valve separates a flow chamber from a valve operating chamber, said valve seat being located in said flow chamber intermediate said intake and discharge ports, said valve being formed with a throttling passage of much smaller flow section than said ports and said chambers, said passage connecting said operating chamber to said intake port.
 4. An arrangement as set forth in claim 3, wherein said means for generating a pressure differential include a pilot valve operatively interposed between each valve operating chamber and one of said low-pressure conduit means, said single operating means include a cam shaft, a plurality of cams mounted on said cam shaft for rotation therewith and respectively associated with said pilot valves, and motion transmitting means connecting each cam to the associated pilot valve for opening and closing the pilot valve when the cam shaft is turned.
 5. An arrangement as set forth in claim 4, wherein said operating means include manual means for turning said cam shaft.
 6. An arrangement as set forth in claim 4, wherein said operating means include a motor, coupling means interposed between said motor and said cam shaft, and coupling operating means responsive to the duration of said first stage for engaging said coupling means after a predetermined period of water flow from said pump through said filter to said pool.
 7. An arrangement as set forth in claim 6, further comprising pump control means for controlling the operation of said pump, said coupling operating means including a first wheel, a speed reducing transmission interposed between said motor and said first wheel for turning said wheel about an axis, a plurality of engaging members circumferentially mounted on said wheel for movement of each engaging member between an operative and an inoperative position, a second wheel, each engaging member when in the operative position and when said first wheel is in a predetermined angular position engaging said pump control means for causing operating of said pump and engaging said second wheel for angularly indexing said second wheel, and motion transmitting means responsive to the angular position of said second wheel for engaging said coupling means.
 8. An arrangement as set forth in claim 7, wherein said coupling means include a coupling wheel secured on said cam shaft against rotation while axially movable on said shaft toward and away from an axial position of driving engagement with said transmission.
 9. An arrangement as set forth in claim 8, wherein said coupling wheel has a gear rim forMed with a gap free from gear teeth, said rim being adapted to mesh with said transmission in said position of driving engagement, said coupling wheel being rotated through substantially 1 revolution by the meshingly engaged transmission.
 10. An arrangement as set forth in claim 1, said timed sequence including a third stage in which flow of water is directed by said control valves directly to said waste line. 